The zener al the zener al shares its all round ride capabilities with its lightweight carbon sibling the zener both models shares the same carbon fork with the befit of lightweight and carbons road vibration dampening properties the al is for aluminium our choice of frame material aluminium keeps the price down and still offers a lightweight option shimano 105 drivetrain light action vivid shifting is just one of many features taken from shimanorsquos top end groupsets making the 105 11